In WO 02/18802A1 an arrangement is described that is mainly adapted for a tool shaft that has a telescopic function. The arrangement includes a tubular shaped element, an inner and an outer, that can be locked relative to one another. The locking is done with the help of a locking member that is securely mounted on the end of the outer element. The opening of the lock is done with the help of a maneuvering member at the other end of the outer element. The transfer of the opening forces is done with the help of an affecting member between the two ends on the outer element. In the description a number of different variations of affecting members are suggested. The preferred embodiment of the affecting member is a thin steel band that is inserted between the inner and the outer elements.
This embodiment functions well but is costly to produce. Not only is the cost for the band that requires openings and cutting high but also the mounting is cumbersome and time-consuming. None of the remaining variations of the affecting members that are hitherto known result in any substantial reduction of the production costs. In addition to the locking details, the tube system accounts for a major portion of the costs. Especially the outer element is costly. One reason is the demanding requirements of durability and the surface on the outer tube. The outer element is usually manufactured of hardened aluminum that has been surface treated in a certain way. It must be able to endure normal handling without being damaged which requires a thickness of at least one millimeter. Furthermore, it is desirable that the surface is painted since it is used for gripping. Anodized surfaces are also used but are experienced as being cold to hold.
The object of the present invention is to achieve an arrangement according to the ingress that makes it possible to manufacture at substantially lower costs compared to earlier known variations.
This object is achieved by the locking arrangement that has two elements that are slidable into one another such as a shaft for a tool where the length is adjustable. The shaft has a locking member at an outer element of one end. The locking member is maneuverable with a maneuvering member that is at a distance from the locking member in a direction towards the other end on the outer element via an affecting member that is slidable along or rotatable about an axis that is parallel to the lengthwise axis of the outer element. The affecting member includes a tube that is made of a polymeric material. The tube encloses the outer element and the outer element has a thin walled, untreated tube of metal, preferably hardened aluminum.